Title makes it sound like a new method of generating energy was discovered, but really the article is about using geothermal in a new location.

> The development of medium-deep (>400 m) and deep geothermal reservoirs (> 1,500 m) could be a partial solution to provide renewable heat to single buildings, residential or commercial neighbourhoods, or districts of the city of Aachen via the existing district heating network.

Ta-daa. That happens. They found some new geothermal source in Munich as well after I moved into the place I'm in now. It turned out it was very viable.

Nowadays the heat in my apartment is mainly geothermal (The district heating network in my neighborhood has been converted to geothermal energy over the past 10 years.)